As my confidence grows in my Phantom 4, today I tried my first real maneuvering in the wild today (as opposed to practicing in safe locations close to home).   I was at the site of a covered bridge over a stream and had just successfully flown back and forth through the full length of the bridge a couple of times with no issues -- the P4 performed flawlessly.  Then a friend suggested that I fly it under the bridge.    Stoked and feeling confident from my successful through-the-bridge crossings, I foolishly reasoned that it would be no problem, despite the nature of the task being entirely different (and, as I reaize now, much more risky).   
  
I deftly flew down the bank on the downstream side of the bridge and yawed the bird to the left 90 degrees to point upstream under the bridge a few feet over the water in one smooth move.   Thinking I could hover there for a minute while I used  FPV to see if it was safe to cross under the bridge, my pride soon shattered when I suddenly realized that my rock solid hover had turned into a rapid downstream backwards drift.  I was still standing on top of the bank, and dense tree and plant growth lined both sides of the creek, so LOS was broken as it drifted out of sight, and I forgot all about FPV in my panic.  Worried that I would end up with a wet unsalvageable bird as the situation unfolded too quickly for my inexperienced brain, I brought the right stick to the left so it would bring the bird back to the bank, and I heard it crash onto the bank downstream of my line of sight.      

I scrambled down the boulder-dense overgrown steep bank to spy the Phantom perched sideways on a couple of boulders on the bank with plants growing through it.  The battery, still with glowing green lights, had slid out about a third of an inch from the fuselage from the impact, but the bird did not have a scratch on it, and none of the rotor blades were chipped or broken.    It must have collided with the shrubs and fallen a short distance to the rocks, meaning I caught an extremely lucky break.


After a very thorough inspection and wipe down of the aircraft, battery, and all of the prop blades (there was some muddy/dirty residue from its short-lived bushwacking adventure), a quick follow up test flight in a nearby empty field proved everything was okay, including the battery.   

My guess is that the VPS tracked the movement of the creek, which was moving at a good clip, resulting in the strong downstream backwards drift.   I know that we are supposed to turn VPS off before flying over water, but in my haste I neglected to remember that.  I had not read that VSP will track with moving water, but it makes sense, especially when trying to hover just a few feet above the water. This was my first attempt at flying over water, and not a well-chosen task for that experience.  I would not recommend the maneuver I tried without much more experience flying in tight situations manually.  And a spare $1400, just in case.  

Anyway, lesson learned, and my drone lives on.

Can you turn VPS off ?

birdingbilly Posted at 2016-4-7 00:34
Can you turn VPS off ?

Good question -- I know flying in A or S mode disables it, but I don't know if it can be disabled independently.   

The VPS could not be turned off in Phantom 4 and hope this tutorial link will help you :

Same question. Can it be turned off without entering P or S mode?

Dirty Bird Posted at 2016-4-9 00:44
There is no means to disable VPS on a P4 that I have found.  I should add that I fly over water all  ...

Correct, although I have sent an email requesting it but it may be what it is.
The manual explains the limitations.

DJI-Paladin Posted at 2016-4-7 15:51
The VPS could not be turned off in Phantom 4 and hope this tutorial link will help you :
https://www ...

I'm guessing this video was created for the P3 because at the end it tells you how to disable VPS.

BouldersDad Posted at 2016-4-8 09:58
I'm guessing this video was created for the P3 because at the end it tells you how to disable VPS.

It's a bit of a bummer not being able to disable it.  

It there any possibility that what I experienced was caused by VPS trying to stay "still" over the stream by tracking with the water surface (or perhaps leave/etcs floating on the surface), or was it a mere coincidence that the phantom hover took off in the direction of the stream flow?  

I do not want to be negative here, but I feel cheated by DJI from not letting me express my Creative Freedom (as they put it in PR stuff)!

I was able to get really close to water surfaces, waterfalls, etc. with my P3 Pro (which I sold to fund a "much better" P4). When I say close I mean 1-2 meters above the surface of the water, with my GPS on and my VPS Off.

Now that I see that even their manual tells not to fly over water, I am curious to see how many creative filmmakers will be able to do this with no GPS signal for long periods of time (28 minutes flight time right?)

I've flown over 200 flights over water with my phantom 3 and a bunch with the phantom 4. Also over water. Never one problem.  

edbighi@gmail.c Posted at 2016-4-8 17:41
I've flown over 200 flights over water with my phantom 3 and a bunch with the phantom 4. Also over w ...

So my current understanding is that VPS cannot be disabled in any mode.   Bottom line, if you are flying low over water, be sure you are ready to manually counteract any VPS side-effects that are possible when doing this.   I would change the title of this thread to reflect that understanding if I could.  My apologies if I mislead anybody.

In my case, I had little room and time to react, and I lacked the skill needed to so so quickly enough.     

Hopefully DJI comes out with an update that lets us disable VPS.  For now, be careful when flying over water!   

almost lost my P4 too yesterday on a real estate job. Same fast drift over water while framing a shot. From now on, sport mode for me to shoot above water. P3 was ok but vps was to 3m and could be disabled. With p4 that's 10m and can't be disabled? please update!

I never have a rat's ass about any issues spoken about on the forums and started flying over ocean. I have yet to experience a problem in over 200 flights with sensors in. Same for phantom 4 and about 20 flights over water now.

edbighi@gmail.c Posted at 2016-4-11 14:28
I never have a rat's ass about any issues spoken about on the forums and started flying over ocean.  ...

Have you flown over flowing water?  My experience was that whitewater over boulders was mostly ok.  Calm flowing water with only small waves/ripples however did cause significant drift of the P4.

Get comfortable with atti mode and drifting will never be a problem.

edbighi@gmail.c Posted at 2016-4-11 18:38
Get comfortable with atti mode and drifting will never be a problem.

How about when the wind is blowing hard and your concentrating on framing a shot?  Automation is there to make it easier for one person to do it all.  There is plenty of automation making it easy for you to fly in ATTI that you couldn't handle  manually.

Expecting someone to fly manually is not an answer to the issue that DJI left a selection off the P4 that was available on the P3 and it doesn't seem there is a good reason to take that control away from the user.

edbighi@gmail.c Posted at 2016-4-11 17:28
I never have a rat's ass about any issues spoken about on the forums and started flying over ocean.  ...

Can you be more specific about your flights. I guess what pilots like are worried about is when you fly below 10 meters. If you owned a P3 in the past, the VPS only worked under 3 meters and could be turned off. Now we have to deal with all sorts of risks that were not in place before.

If you have 200 flights with the P4, how many of those were under 10-5 meters, how many you tried to hover over foaming water, etc. I would welcome any advice from a seasoned 200+ flights over water.

Aside from drift, could the aircraft suddenly  drop height during hover? Thanks!

parkgt Posted at 2016-4-11 21:16
How about when the wind is blowing hard and your concentrating on framing a shot?  Automation is t ...

Its just a guess....but perhaps the extra sensors etc.  Would this be a challenge in the firmware to have this option like the P3?      Personally for me?   I will just fly above 50 feet if I am over water for now  and call it a day   

Ok, I understand the VPS won't work if you are over water.  I do plan to take my Phantom 4 to the VI in May.  If I stay over 10M while it is over water will It be ok?

edbighi@gmail.c Posted at 2016-4-11 17:28
I never have a rat's ass about any issues spoken about on the forums and started flying over ocean.  ...

I think they mean real low level over water. vs. normal altitude flights.

think skimming the waves ...1 to 4 foot above creek bed

I still would like to see the ablility to turn VPS off in a firmware update as well. The Phantom 4 seems to operate all right as long as the water is calm. I shot this (first shot in the video) last night at a height of 1-2 feet from the surface of the water with no issues. But I would be a lot more careful over moving water (a shoot I plan to do soon).

I haven't tried it yet but several people have reported that sticky tape is a good way to turn off VPS. Like I said, not personally confirmed so try at your own risk.

connorschulte Posted at 2016-4-8 10:36
Same question. Can it be turned off without entering P or S mode?

It cant be turned off at all on the Phantom 4. Not even in S or A modes.

the VPS on my Phantom 3 resulted in the same type of behavior.  I was lining up a shot that was just over a fence between two trees, tight shot but plenty of room.  The ground is level but then dips before the fence.  As  I was slowly gliding it along I was at the perfect height to clearly make it through the shot.  But as I moved forward and the ground began to dip I watched my phantom move forward and begin decending.  In a minor panic I pulled back before hitting the fence but ended up running it into the ground behind it since the phantom decided to descend lower than the bank of the hill.  Only resulted in broken carbon fiber props but for the next minute my phantom though a motor was obstructed.  Some dirt got tossed in, after cleaning it out its worked perfect but still.  the VPS has literally done more harm for me than any good